Multiple position switches are used in many applications. For example, multiple position switches, commonly referred to as joy stick switches, are widely used for electronic games and the like. Such switches also are found in the steering control devices for self propelled electric wheel chairs. Computers frequently employ multiple position or multi-direction switches for controlling the movement of a cursor on a computer display screen.
Five patents which are specifically directed to multi-position or multi-directional switch mechanisms are the U.S. Pat. Nos. to Chandler 4,246,452; Smith 4,408,103; Main 4,428,649; Nakayama 4,476,356; and Shirai 4,687,200. All of these patents disclose the use of a central actuating lever of key which is pivoted or tipped about a central point to close switch contacts located in a circle around this central point. The operation of the mechanisms disclosed in all of these patents is substantially the same. A resilient member of spring is used to return each of the actuating levers of the switches of these patents to a rest or neutral position. Separate metal springs are used for this purpose, with the exception of the Shirai and Smith Patents which disclose the use of a resilient circular elastomeric member to provide the return spring function. In all of these patents, the pivot portion comprises either an extension which is formed as an integral part of the switch actuating lever, or is formed as an integral part of the base or bottom of the housing in which the switch is located. It has been found that the plastic projections forming the pivots in the devices disclosed in these patents typically have a substantial amount of friction which reduces the quickness of the response of the switch. In addition, when the switch undergoes extensive use, significant wear frequently is encountered in the pivot of such integrally molded parts.
It is desirable to provide a multi-position electrical switch which incorporates the advantages of the prior art devices and which reduces friction and wear.